3 Claims. (Cl. 221-148) This invention relates to an improved dropper for medical and other uses.

The ordinary medicine dropper has the disadvantage when it is desired to measure a certain number of drops of medicated solution that it requires a great deal of practice in order to obtain the right number of drops and not to exceed such number. In particular, droppers of known design are objectionable because of the fact that the speed or number of drops discharged depends on the inclination at which the dropper is held, that-is if held vertically-a steady stream of drops or fluid will flow at a high rate, while when the dropper is held at an inclined P s n the speed and number of drops will bedecreased accordingly.

With the dropper of this invention only one drop at a time can be obtained and the rate of discharge of the drops is rendered substantially independent of the angle of inclination at which the dropper is held, thus ensuring an exact amount of medicated or other fluid to be administered even in the hands of unskilled persons. Of course. the dropper according to the invention is not limited to medical use but may be employed with equal advantage for other purposes, such as in chemical laboratories where accurate measurement of small quantities of a fluid substance is required.

The invention will be described in detail with reference to the accompanying drawing forming part of this specification wherein Figure 1 is a vertical cross-sectional view of a dropper embodying the improved features of the invention; and

Figure 2 is a partial view of the dropper according to the preceding figure shown in inclined position to illustrate the advantages and novel results obtained-by the invention.

In the drawing, item It is a tube of glass or other suitable material the lower end of which terminates in a ball or sphere ll preferably of the same material and integral with the tubev Ii. This sphere which advantageously has a diameter equal to or somewhat greater or less than the diameter of the tube ill may be either solid as shown or hollow and is separated from the tube proper by a constricted portion l2 provided with atleastone or preferablya series of discharge openings or port Ill. The openings l3 which are preferably spaced by equal angles and of which four are shown in the example illustrated spaced at 90- from each other willallow a fluid l'l in the tube iii to discharge and flow 'along'the spherical surface ll so as to accumulate on the lower Part of the latter to form a drop as indicated at IS. The size of the dropsbefore disengaging the sphere II will be substantially determined by the physical characteristics, such as the viscosity of the liquid Il and the surface tension between the liquid and the material of the sphere. The size of the drop and in turn the number of drops discharged per second willbe substantially independent of the angle of inclination of'the dropper by virtue of the uniform spherical surface on which the fluid has to. pass after leaving the ports l3 before accumulating into a drop as will be more clearly understood by reference to Figure 2 showing the dropper in an inclined position. Item i4 is a collapsible rubber bulb clamped over the flanged upper edge It or the tube Ill for introducing and discharging the fluid by expansion and compres Zion, respectively, of the bulb H in a manner well nown.

There is provided, therefore, by the invention a dropper which provides not only a constant number of drops per unit of time independently of the angular position or inclination at which the dropped is held but which also insures each of the drops to be of exactly the same size determined by the diameter of the spherical discharge surface as will be readily understood from the foregoing." This makes it possible to accurately calibrate the dropper such as by a calibration scale applied to the tube l0 both for the number of drops as well as the amount of liquid discharged for a given size of dropper or discharge surface, respectively. In this manner, counting of the number of drops and attendant error due to the human factor are eliminated.

In place of the collapsible rubber bulb I4 for filling and discharging the dropper any known equivalent arrangement such as a piston mov-, me within the tube It may be provided or liquid may be fed to the tube continuousl to act as a constant drip feed in scientific and industrial apparatus to make up for solvent evaporated or constituent substances'lost in a solution and similar purposes well understood.

It will be evident that the invention is not limited to the speciflc details of construction shown and disclosed for illustration but that modificationsv and changes may be resorted to coming within the broader scope of the invention as defined in the appended claims.

Iclaim:

1. A dropper comprising a rigid tube, a collapsible bulb secured to one end oi said tube,

the opposite-end of said tube being of restricted diameter and terminating in a spherical head. the restricted portion adjacent to said head being provided with at least one opening adapted upon compression of said bulb to cause a fluid in' said tube to pass over the surface of and accumulate in successively discharged drops at the bottom of said head.

2. A dropper comprising a rigid tube, a collapsible bulb secured to one end 0! said tube. the opposite end of said tube being of restricted diameter and terminating in a solid spherical head of the same material and integral with said tube, the restricted portion oi said tube adjacent to said head being provided with at least one opening adapted upon compression or said 5 V bulb to cause a fluid in said tube to pass over the surface or and accumulate in successively discharged drops at the bottom of said head.

3. A dropper comprising a rigid tube, a. 1.

5 lapsible bulb secured to one end of said tube.

the opposite end of said tube being or restricted diameter and terminating'in a spherical head, the restricted portion'oi said tube adjacent to said head being provided with a plurality of 10 openings equally anguiarly spaced adapted upon compression 01 said bulb to cause a fluid in said tube to pass over the surface of and accumulate in successively discharged drops at the bottom 0! said head. 7 WILLIAM DUBILIER.